Do you want to live a longer life in good health? Simple practices can make some difference, such
as exercise or calorie restriction. But over the long haul all that really matters is progress in medicine:
building new classes of therapy to repair and reverse the known root causes of aging. The sooner these
treatments arrive, the more lives will be saved. Find out how to help »

10

Jan

2008

Naked Mole-Rats and Negligible Senescence

This paper indicates well why the biochemistry of naked mole-rats is attracting attention, now that more researchers are of the mindset that aging can be successfully - and greatly - manipulated through biotechnology and medical science. If you're intending to improve human biochemistry to enable greater healthy longevity, it makes sense to look at existing examples that are already better in that respect.

Aging refers to a gradual deterioration in function that, over time, leads to increased mortality risk, and declining fertility. This pervasive process occurs in almost all organisms, although some long-lived trees and cold water inhabitants reportedly show insignificant aging. Negligible senescence is characterized by attenuated age-related change in reproductive and physiological functions, as well as no observable age-related gradual increase in mortality rate. It was questioned whether the longest living rodent, the naked mole-rat, met these three strict criteria.

Naked mole-rats live in captivity for more than 28.3 years, approximately 9 times longer than similar-sized mice. They maintain body composition from 2 to 24 years, and show only slight age-related changes in all physiological and morphological characteristics studied to date. Surprisingly breeding females show no decline in fertility even when well into their third decade of life. Moreover, these animals have never been observed to develop any spontaneous neoplasm. As such they do not show the typical age-associated acceleration in mortality risk that characterizes every other known mammalian species and may therefore be the first reported mammal showing negligible senescence over the majority of their long lifespan.

The proposal focuses on three organisms (in order of priority): the naked mole-rat (Heterocephalus glaber) whose record longevity of 28.3 years makes it the longest-lived rodent, the white-faced capuchin monkey (Cebus capucinus) which can live over 50 years, and the bowhead whale (Balaena mysticetus), the longest-lived mammal with an estimated longevity of over 200 years. If approved, these organisms will be added to the queue of target organisms to be sequenced, the sequencing will be carried out in one of the NHGRI-funded sequencing centers, and the entire genome sequences will be deposited in free public databases.

The trend in resources devoted to more goal-oriented aging research will only continue as new science moves the conservative, consensus position towards the feasibility of engineered healthy life extension. Initiatives like SENS that are more promising than metabolic re-engineering - in terms of time to produce results, and the level of life extension that can be plausibly attained - also have the chance to benefit from this growing level of support in the scientific and funding communities.

All of Fight Aging!, with the exception of the
introductory articles, is published under the
Creative Commons Attribution 4.0 International License.
In short, this means that you are encouraged to republish and rewrite
Creative Commons licensed Fight Aging! content in any way you see fit. We
only ask that that you are polite and (a) link to the original,
(b) attribute the author, and (c) attribute Fight Aging!.